Nonadiabatic Effects in Photodissociation of Small Molecules

理论与计算化学专业 化学部支持全面调查 化学反应中的曲线交叉事件 由托莱多大学的郭教授完成。郭教授 正在进行一项非绝热转变动力学的研究， 小分子的光解离，包括新的 三维量子力学计算 碘代烷在气相中的光解动力学。 郭教授的新方法处理的解离度 自由度的量子波包方法，同时表征 环境运动的经典轨迹。 量子和 经典的子系统通过Escherichfest方案耦合， 波包和轨迹可以传播 自洽。 %%% 大多数化学反应都可以理解为 包括反应物和产物分子 电子国。 然而，有许多重要的 反应，包括大多数由 紫外线辐射，反应过程涉及 基态和激发态之间的相互作用。 一种新的理论方法正在测试中， 预测这些过程的概率，从而 有助于理解过程的机制 由光引发。

The Theoretical and Computational Chemistry Program in the Chemistry Division has supported a comprehensive investigation of curve-crossing events in chemical reactions being carried out by Professor Guo at the University of Toledo. Professor Guo is conducting a study of non-adiabatic transition dynamics in the photodissociation of small molecules, including new three-dimensional quantum mechanical calculations of the photodissociation dynamics of alkyl iodides in the gas phase. Professor Guo's new approach treats the dissociation degree of freedom by a quantum wavepacket method while characterizing environment motions by classical trajectories. The quantum and classical subsystems are coupled via the Ehrenfest scheme so that the wavepacket and the trajectory can be propagated self-consistently. %%% Most chemical reactions can be adequately understood as involving reactant and product molecules in their ground electronic states. However, there are many important reactions, including most processes that are initiated by ultraviolet radiation, for which the reaction process involves interaction between the ground and excited electronic states. A new theoretical method is being tested that should permit prediction of the probability of such processes and thereby contribute to the understanding of the mechanisms of processes initiated by light.